Apparatus for operating alarms or other device



G. I. ROCKWOOD. APPARATUS FOR OPERATING ALARMS OR OTHER DEVICES.

APPLICATION, mum rnniz, 1910.

1,033,472. Patented July 23, 1912.

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J2 forney UNITED STATES PATENT carton.

GEORGE I. OF WORCESTER, MASSACHUSETTS APPARATUS FOB OPERATING ALARMS 03 mm DEVICE Specification of Letterl Patent.

Patent/ed may 23. 1912.

H Application filed February 2,1910. Serial No. 541,631.

accompanying drawings, is a specification.

My present invention relates to an alarm operating device which is especially adapted for initiating the operation of an alarm employed in connection with an automatic fire sprinkler, to be operated by a continuous passage through a pipe of liquid under pressure, but is ineffectual during short intermittent passages of liquid.

The apparatus in which'myinvention is embodied causes the alarm to be sounded whenever one or more sprinkler heads have been/released. causing a continuous flow of water through the supply pipe, but remaining inefi'ectual to operate the alarm during intermittent passages, of water through the supply pipe, such as are caused by what are known as water hammers.

It is the object of my present invention to insure the certain and positive operation of the alarm whenever relief is given to the pressure in the supply pipe. such as would occur by the release 0 a single sprinkler headf This object is accomplished by the construction and arrangement of parts as described in the following specification and illustrated in the accompanying drawings forming a part of the same. in which- Figure l is a side elevation of my improved alarm controlling mechanism. the principal parts being shown in vertical central sectional view. and-Fig; 2 is a vertical central sectional view on an enlarged scale of the differential diaphragm.

Similar reference characters refer to similar parts in the different figures.

Referring to the accompanying drawings, 1 denotes a chamber having an inlet passage Qcommunicating with a pipe leading to a water supply under pressure. The chamber 1 is provided with an outlet passage 4 communicating with a pipe 5 forming the supply pipe of a fire sprinkler system. \Vhen the sprinkler heads are closed. as in the normal condition of the system. the low of water from the'watcr supply through the pipes and and the chamber l l. chcchcd.

'in the pipe 3 by in which the alarm is arranged.

phragm 12 is but whenever one or more sprinkler heads are released, water under pressure will pass through the pipes 3 and 5 1 in an uninterrupted flow and, under this condition, it is desirable te sound an alarm, which I accomplish by means of an alarm sounding mechanism, comprising a check and the chamber valve 6 supported upon an annular valve seat 7, said valve being normally held upon its seat and against the pressure of water means of the water pressure above the check valve 6 and between it and the sprinkler heads. As the area of the check valve 6 exposed to water pressure from above is greater'than the area exposed to water pressure from below, a. pressure of water above the valve somewhatless than the pressure of water below will be sutlicient to hold the check valve '6 uponits seat.

\Yhenever one or more sprinkler heads are released, however, the pressur above the check valve becomes relieved, a wing the valve to be lifted and an uninterrupted flow of water to pass to the sprinkler heads.

The valve seat 7 is provided with an annular groove or recess 8, communicating with a pipe 9 which communicates with a. chamber 10 inclosedbetween a cap 11 and a flexible diaphragm 12. During the temporary lifting of the check valve 6 by what is known as a water hammer, a water will be forced into and. as the latter becomes filled. the flexible diaphragm 12 is raised. thereby lifting the attached tube 13 until its beveled end fills the o ening 1-1 leading to the upper chamber 15. If water continues to be admitted by sucdessive water hammers into the chamber 10. it will be forced upward through the tube 11) and restricted opening 16 into the chamber 15. and this upward movement of the water into the chamber 15 will continue until the pressure beneath the diarelieved sutlicientl v to allow a spiral spring .17 to force the diaphragm 12 and tube 13 downward. allowingthe water which has accumulated in the chamber 15 to flow through the opening 14 into the lower chamber 18 and escape through a pipe 19. Temporary accumulations of water in the chamber, due to a water hammer. will. therefore. escape through the pipe 1 .\n uninterrupted flow of water to the sprinkler system. such as would occur whenever oneor more sprinkler heads had been quantity of the chamber 10 N3 l: m e w Hzmf hm! ,w tiiaphragm 26 ofi' its valve seat and open the rum: 'g iby pass, it is only necessary that the water pressure above the check valv-ei 6i shall be 1 pressure in the chamber 10 to hold the diaphragm 12 and tube 13 in their elevated positlo-ns, thereby' permanently closing the opening 14 until the water hasfilled the 5 chamber 15 and risen through a pipe to rotate a wheel within a case 21 and carrya series of hammers attached to the rotating shaft of the wheel against a bell or gong 22 thereby sounding an alarm to indicate that one or more sprinkler heads had been released land that water was flowing through thelsuppl pipe 5, t he a ove described alarm apparatus, ,eomprisin the, chamber'ol with'its check Fa1ve-6 an thechambers 15 and 18 with the mechanism for controlling the accumulation of water, forms; no part of my presentinvent-ion, the same having been fully described and claimed in a copending applim ration filed by me on December. 3, 1909,;'Se-

rial No. 531 253. v To render the apparatus more sensitive to slight differences in water pressure upon oppositesides of the check valve 6 is the object of my present invention, which consists in forming a by-pass between the water supply pipe 3 and the chamber 10, consisting of a pipe 23 communicating at one end with the watery pipe 3 below the check valve 6, and communicating at its other end with achamber 24 between the lower half 25 of the easing and a flexible diaphragm 26, having its edges clamped between the lower half 25 and the upper half 27 of the casing.

Communicating with the chamber 24 is a pipe 28 leading ;into the pipe 9 which communicates with the chamber 10. A chamber 29, above the diaphragm 26, communicates with the chamber 1 through a short pipe 30. The upper end of the pipe 28 extends slightly into the chamber 24 and forms -a valve seat 31 with which the diaphragm 26v isarranged to contact when the latteris de-' pressed.- During the operation of the apparatus, when the water pressure above the clieckvalve 6 is substantially equal to or greater than the water pressure below the check valve 6 the flexible diaphragm 26 will be forced downward into contact with the 50' valve seat 31, thereb and preventing the the by-pass connecting the chamber 10' with the watersu ply pipe 3. The diameter of thc fiexiblediaphragm 26 is several times gi'eat er'th'an the diameter of the valve seat 31, so that theodifferences in the effective pressures upon the upper and lower sides of V the diaphragm 2.6, when the water pressure mabove and below the check valve 6 1s the i I v In order to lift the til-sane, is very small.

slightly less than the pressure below the check valve, or in an inverse ratio to the closing the pipe 28' ow of water through water contacting surface above and below the flexible diaphragm.

Whenever a slight decrease in the water pressure above the check valve 6 over the pressure below the check valve ta kes place, even by the release of a single sprinkler head, the difference in water pressure upon oppositesides of the diaphragm 26 will be effective in raising the diaphragm from its valve seat 31 and opening the by-pass, al-

lowing water to flow freely through the pipes 23, 28 and--9-into the chamber 10, filling 'the latter and closing the opening 14, causing an accumulation of water in the chamber 15 sufficient to overflow through the pipe 20 and sound the alarm. This will occur even if the valve 6 should have become stuck uponlits'valve seat, or should fail'to open sufficiently to afford a supply of waterthrough the recess 8 and pipe 9. The operation of the alarm, therefore, does not depend upon the lifting of the valve 6, but occurs whenever the diaphragm 26 has been raised from its valve seat 31, and this lifting of the diaphragm will occur with a much less difference in water pressure upon its opposite sides than is required to raise the,

check valve 6, for the reason that, in the case of the check valve 6, the difference in areas of effective water pressures upon op-' posite sides of the valve is comparatively large, while in the case of the flexible diaphragm, the difference in areas of effective water pressures when the diaphragm contacts with the valve seat 31 is proportionately small.

my present lmprovement the operation of the alarm is rendered bot-h certain and extremely sensitive to slight variations in water pressure upon opposite sides of the check valve 6 and, as soon as the by-pass 'is once open by slight variations in water pressure, the flow of water therethrough is suflicie'nt to rapidly fill the chamber 15 to produce an immediate alarm.

When a single sprinkler head alone is released, only a minute lifting of the check valve 6 is necessary to supply suflicient water for the operation of the iopen sprinkler, and frequently a continued rising and falling, or pulsating movement, of the check valve 6 will occur. In neither case is there sufficient water admitted through the pipe 9 to operate the alarm, and the action of the diaphragm 12 under this pulsating movement is similar to that which occurs in the case of 'a water hammer, above described. By my present improvement, however, the opening of even a single sprinkler head will cause the sounding of the alarm, ,which would not take place at all if the check valve 6 were alone depended upon.

I claim, 1

1. In an apparatus of t-heclass descrlbed, comprising a water supply plpe, a casing having a check valve inclosing three chambers one above the other, a diaphragm in the lowermost chamber, an opening between the middle and upper chambers, a valve for closing said opening controlled by the movement of said diaphragm,.a water passage connecting said lower chamber with the water supply pipe below said check valve, a diaphragm arranged to close said water passage, means for maintaining a water pressure on'one side ofi said diaphragm corresponding with the pressure in the water supply pipe below the check valve, and means for maintaining on the opposite side of said diaphragm a Water pressure corresponding with the pressure above the check valve.

2. In an apparatus of the class described, comprisinga water supply pipe provided with a check valve, the combination of a casing incloslng a pressure chamber, a dlaphragm inclosed in said chamber, means for operating an alarm controlled by the move- 'ment of said, diaphragm, a water passage between said pressure chamber and the water supply pipe, a diaphragm arranged to close said passage, means for maintaining a water pressure on one side of said diaphragm corresponding with the pressure in the water supply pipe below the check valve, and means for maintaining a water pressure on the opposite side of said diaphragm corresponding to the pressure in said water supply pipe above the check valve.

GEORGE I. ROCKWOOD. Witnesses:

PENELOPE COMBERBACH, NELLIE \VHALEN. 

